OK, let's work through this together. We're starting with 685 and we're going to multiply it by 139, which means we add 685 to itself 139 times.
Step 1: 0 + 685 = 685
Step 2: 685 + 685 = 1370
Step 3: 1370 + 685 = 2055
Step 4: 2055 + 685 = 2740
Step 5: 2740 + 685 = 3425
Step 6: 3425 + 685 = 4110
Step 7: 4110 + 685 = 4795
Step 8: 4795 + 685 = 5480
Step 9: 5480 + 685 = 6165
Step 10: 6165 + 685 = 6850
Step 11: 6850 + 685 = 7535
Step 12: 7535 + 685 = 8220
Step 13: 8220 + 685 = 8905
Step 14: 8905 + 685 = 9590
Step 15: 9590 + 685 = 10275
Step 16: 10275 + 685 = 10960
Step 17: 10960 + 685 = 11645
Step 18: 11645 + 685 = 12330
Step 19: 12330 + 685 = 13015
Step 20: 13015 + 685 = 13700
Step 21: 13700 + 685 = 14385
Step 22: 14385 + 685 = 15070
Step 23: 15070 + 685 = 15755
Step 24: 15755 + 685 = 16440
Step 25: 16440 + 685 = 17125
Step 26: 17125 + 685 = 17810
Step 27: 17810 + 685 = 18495
Step 28: 18495 + 685 = 19180
Step 29: 19180 + 685 = 19865
Step 30: 19865 + 685 = 20550
Step 31: 20550 + 685 = 21235
Step 32: 21235 + 685 = 21920
Step 33: 21920 + 685 = 22605
Step 34: 22605 + 685 = 23290
Step 35: 23290 + 685 = 23975
Step 36: 23975 + 685 = 24660
Step 37: 24660 + 685 = 25345
Step 38: 25345 + 685 = 26030
Step 39: 26030 + 685 = 26715
Step 40: 26715 + 685 = 27400
Step 41: 27400 + 685 = 28085
Step 42: 28085 + 685 = 28770
Step 43: 28770 + 685 = 29455
Step 44: 29455 + 685 = 30140
Step 45: 30140 + 685 = 30825
Step 46: 30825 + 685 = 31510
Step 47: 31510 + 685 = 32195
Step 48: 32195 + 685 = 32880
Step 49: 32880 + 685 = 33565
Step 50: 33565 + 685 = 34250
Step 51: 34250 + 685 = 34935
Step 52: 34935 + 685 = 35620
Step 53: 35620 + 685 = 36305
Step 54: 36305 + 685 = 36990
Step 55: 36990 + 685 = 37675
Step 56: 37675 + 685 = 38360
Step 57: 38360 + 685 = 39045
Step 58: 39045 + 685 = 39730
Step 59: 39730 + 685 = 40415
Step 60: 40415 + 685 = 41100
Step 61: 41100 + 685 = 41785
Step 62: 41785 + 685 = 42470
Step 63: 42470 + 685 = 43155
Step 64: 43155 + 685 = 43840
Step 65: 43840 + 685 = 44525
Step 66: 44525 + 685 = 45210
Step 67: 45210 + 685 = 45895
Step 68: 45895 + 685 = 46580
Step 69: 46580 + 685 = 47265
Step 70: 47265 + 685 = 47950
Step 71: 47950 + 685 = 48635
Step 72: 48635 + 685 = 49320
Step 73: 49320 + 685 = 50005
Step 74: 50005 + 685 = 50690
Step 75: 50690 + 685 = 51375
Step 76: 51375 + 685 = 52060
Step 77: 52060 + 685 = 52745
Step 78: 52745 + 685 = 53430
Step 79: 53430 + 685 = 54115
Step 80: 54115 + 685 = 54800
Step 81: 54800 + 685 = 55485
Step 82: 55485 + 685 = 56170
Step 83: 56170 + 685 = 56855
Step 84: 56855 + 685 = 57540
Step 85: 57540 + 685 = 58225
Step 86: 58225 + 685 = 58910
Step 87: 58910 + 685 = 59595
Step 88: 59595 + 685 = 60280
Step 89: 60280 + 685 = 60965
Step 90: 60965 + 685 = 61650
Step 91: 61650 + 685 = 62335
Step 92: 62335 + 685 = 63020
Step 93: 63020 + 685 = 63705
Step 94: 63705 + 685 = 64390
Step 95: 64390 + 685 = 65075
Step 96: 65075 + 685 = 65760
Step 97: 65760 + 685 = 66445
Step 98: 66445 + 685 = 67130
Step 99: 67130 + 685 = 67815
Step 100: 67815 + 685 = 68500
Step 101: 68500 + 685 = 69185
Step 102: 69185 + 685 = 69870
Step 103: 69870 + 685 = 70555
Step 104: 70555 + 685 = 71240
Step 105: 71240 + 685 = 71925
Step 106: 71925 + 685 = 72610
Step 107: 72610 + 685 = 73295
Step 108: 73295 + 685 = 73980
Step 109: 73980 + 685 = 74665
Step 110: 74665 + 685 = 75350
Step 111: 75350 + 685 = 76035
Step 112: 76035 + 685 = 76720
Step 113: 76720 + 685 = 77405
Step 114: 77405 + 685 = 78090
Step 115: 78090 + 685 = 78775
Step 116: 78775 + 685 = 79460
Step 117: 79460 + 685 = 80145
Step 118: 80145 + 685 = 80830
Step 119: 80830 + 685 = 81515
Step 120: 81515 + 685 = 82200
Step 121: 82200 + 685 = 82885
Step 122: 82885 + 685 = 83570
Step 123: 83570 + 685 = 84255
Step 124: 84255 + 685 = 84940
Step 125: 84940 + 685 = 85625
Step 126: 85625 + 685 = 86310
Step 127: 86310 + 685 = 86995
Step 128: 86995 + 685 = 87680
Step 129: 87680 + 685 = 88365
Step 130: 88365 + 685 = 89050
Step 131: 89050 + 685 = 89735
Step 132: 89735 + 685 = 90420
Step 133: 90420 + 685 = 91105
Step 134: 91105 + 685 = 91790
Step 135: 91790 + 685 = 92475
Step 136: 92475 + 685 = 93160
Step 137: 93160 + 685 = 93845
Step 138: 93845 + 685 = 94530
Step 139: 94530 + 685 = 95215

So, 685*139 = 95215